On Wed, 11 Nov 2009 09:11:02 -0700 Sergey Manucharian <sergeym@xxxxxxxxx> wrote: > Hi folks, > > The similar question most probably has been discussed many times, but > I really cannot find a clear answer. There are some obvious thinks > like 64-bit addressing, but how about math calculations performance? > > I've set up two identical virtual machines in vbox - one with Arch > x86_64 and another with Arch i686. I ran mencoder in both over the > same video and got the following figures: > > x86_64: 43 sec > i686: 34 sec > > which make x86_64 not so impressive ;) > > Some time ago I read an article at AMD web site, they suggested using > their math libs for writing programs instead of standard ones. In such > a case a program with complex math involved can performs much better > (personally I haven't tried). > > I'm just curious about other people's opinions on this subject. > > Cheers, > Sergey > Like most people have already said, benchmarking using virtual machine is not a good idea as the results will most likely _not_ reflect the actual performance. Better to install both Arch 32-bit and 64-bit on the same machine (dual boot) and run the tests. I've used 32-bit Arch Linux in the past before switching to 64-bit and from my personal experience certain operations, such as video/music encoding, is a _lot_ faster on 64-bit. I didn't timed it back then, but it was almost twice faster than on 32-bit. Regards, Smith
